Existing coding techniques mainly include two parts: source coding and channel coding. Regarding the source coding, because conventional networks use circuit switch, the source coding is typically at a fixed rate in the conventional networks. In the field of IP phone born over the Internet, Adaptive Multi-Rate (AMR) techniques can be used to change the coding rate of a user, and the change of the coding rate is usually controlled based on network resource conditions, such as network bandwidth, etc.
Regarding the channel coding, the mode thereof is mainly set according to a service type. For example, Adaptive Modulation and Coding (AMC) is one of the techniques used in the channel coding, and adaptively changes the modulation and coding manner according to channel conditions. Herein, the channel conditions may be estimated by the Channel Quality Indicator (CQI) feedback scheme of a receiver. The AMC technique is widely used in wireless communication systems such as mobile communication systems and Digital Video Broadcasting (DVB) systems so as to improve transmission efficiency and capability of the system. In specific applications, depending on different service types, a VoIP user is set as not using the AMC and a Data user is set as using the AMC. This results in a problem that resource usage efficiency of the VoIP user is low, which may lead to potential wireless resource waste.
As can be seen, an appropriate coding technique may be greatly desired for reasonable resource usage.